This section provides background information related to the present disclosure which is not necessarily prior art.
At present, relays are widely used in appliance control technology. The rated voltage for driving a relay is normally lower DC voltage, e.g., 5 VDC, 12 VDC, or 24 VDC, etc. DC voltage is provided to the relay to make sure the relay is in normal operation. But in a system powered by an AC power supply, an additional DC power supply is needed for driving coils of the relay with the DC voltage. The additional DC power supply increases costs.
Presently, a switching mode power supply (SMPS) is used to step down the AC line voltage to a lower DC voltage, or a linear transformer is used to step down the AC line voltage to a lower AC voltage. Then, a DC voltage for the relay is produced by the regulating diodes and capacitors. But the switching mode power supply or the linear transformer also increases costs.